US 4,232,870 AGranted

Clamping device for a rotatable information carrying record

AssigneeU.S. Philips Corporation

InventorJohannes A. Iemenschot

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Abstract

For driving a video record on a video player use can be made of a clamping device which comprises a drive spindle on which record supporting means are disposed which inter alia comprise: a centering member, having a centering surface whose transverse dimension varies from smaller than to greater than the diameter of the record hole, which centering surface, also during operation, co-operates with the edge of a record hole; a record loading device which during operation presses the edge of the record hole against the centering surface; and record carrying means which frictionally co-operate with the video record and which are disposed at some radial distance from the centering member. In accordance with the invention the record carrying means comprise a record carrying member which as a whole is axially movable between an upper and a lower position, which member by means of a parallel guidance is accurately coaxially movable relative to the centering member, the positioning surfaces for the frictional co-operation with a video record to be played being rigidly connected to the record carrier member and being disposed in a plane, which, regardless of the axial position of the record carrying member relative to the centering member, is always perpendicular to the axis of rotation of the drive spindle. Resilient means are provided for urging the record carrying member towards its upper position.

Claims2

Dependent claims

A clamping device for clamping a rotatable disc-shaped record carrier provided with a center hole into position, comprising:

a drive spindle having a driven end and a free end, and being rotatable about an axis of rotation and axially immovable;
a centering member pivotable about said axis of rotation and being provided with a centering surface whose diameter varies from smaller than to greater than the diameter of the record hole, said centering surface being in contact with the edges of said record center hole during the rotation of the record and said centering member being axially immovable;
record loading means movable to a position opposite the centering member and bearing on the record in this position for pressing the centering surface against the edge of the record center hole;
record carrier means provided with a record support surface radially spaced from said centering surface of said centering member for immediately confining said record carrier to a position perpendicular to the axis of rotation of said drive spindle, and for lowering the record carrier onto said centering surface while maintaining the perpendicular relationship between the record carrier and the axis of rotation of said drive spindle during axial and rotational motion of the record carrier means;
and means for axially resiliently biasing the record carrier means toward the record carrier with a force less than that necessary to overcome the weight of the record combined with the pressing force of the record loading means, thereby facilitating the lowering of said record carrier.

2 more elements

Dependencies are inferred from the claim text.